Image sensors convert optical light to an electrical signal. Conventional image sensors are used predominantly in digital cameras, and may fall into one of two categories: charge-coupled device (CCD) image sensors and complementary metal-oxide-semiconductor (CMOS) image sensors.
Image sensors are formed from an array of pixels, each of which is converts received light into an electrical signal. Image sensors may include arrays of microlenses positioned above the pixels in order to focus the light received by the pixel. The effectiveness of a pixel at converting received light into an electrical signal is dependent at least in part on the amount of light received in the photodetector region of the pixel. Thus, improvements are desired that focus light toward the photodetector region of a pixel.